Frequency hopping method for machine type communication

ABSTRACT

A method and apparatus may include receiving, by a machine type communication user equipment, parameters for frequency hopping in downlink or uplink. The parameters comprise an “X,” ‘Y,” and “Z” parameters, “X” corresponds to a duration for which the same physical resource blocks are used for transmission. ‘Y” corresponds to a frequency hopping period, and “Z” corresponds to a frequency hopping pattern indication. The method may also include performing frequency hopping in accordance with the parameters.

BACKGROUND Field

Embodiments of the present invention relate to a frequency hoppingmethod for machine type communication.

Description of the Related Art

Machine type communication (MTC) is wireless communication that seeks tocommunicate with devices by using new modulation/signal processingtechniques. MTC has been described by the 3th Generation PartnershipProject (3GPP), and is based upon previous network technologies. Sinceits inception, MTC has seen extensive deployment in a wide variety ofcontexts involving the communication of data.

SUMMARY

According to a first embodiment, a method may include receiving, by amachine type communication user equipment, parameters for frequencyhopping in downlink or uplink. The parameters may include an “X,” “Y,”and “Z” parameters. “X” corresponds to a duration for which the samephysical resource blocks are used for transmission. “Y” corresponds to afrequency hopping period. “Z” corresponds to a frequency hopping patternindication. The method may also include performing frequency hopping inaccordance with the parameters.

In the method of the first embodiment, the one or more parameters forfrequency hopping are broadcast, configured via radio resource controlsignalling or configured via Layer 1 (L1) signalling.

In the method of the first embodiment, “X” and “Y” are based on physicaldownlink shared channel or machine type communication downlink controlchannel or physical uplink shared channel or physical random accesschannel repetition levels.

In the method of the first embodiment, “X” is based on a channelestimation filter length.

In the method of the first embodiment, “Y” corresponds to ceiling (K/n),“K” corresponds to a number of repetitions, “n” is an integer greaterthan or equal to 2, and “n” is the number of hops in one datatransmission configured by an evolved Node B.

In the method of the first embodiment, the values of “X” and “Y” are thesame for all repetition levels. The number of hops is determinedaccording to the repetition number of the related repetition level and“Y”.

In the method of the first embodiment, “X” corresponds to Y−1.

In the method of the first embodiment, “Z” is based on an offset or apredefined pattern for physical downlink shared channel or machine typecommunication downlink control channel or physical uplink shared channelor physical random access channel frequency hopping.

In the method of the first embodiment, the predefined pattern includeshalf-bandwidth frequency hopping or one-fourth-bandwidth frequencyhopping.

In the method of the first embodiment, “Z” is the index of a pattern ofpre-defined PRB blocks, where 6 PRBs constitute a PRB block, forphysical downlink shared channel or physical uplink shared channelfrequency hopping.

In the method of the first embodiment, “Z” is the index of anyconsecutive 6 PRBs, for physical downlink shared channel or physicaluplink shared channel frequency hopping.

In the method of the first embodiment, the position of frequency hoppingis indicated by DCI, where additional bits provide the information ofthe position of the 6 PRBs for each hop.

In the method of the first embodiment, “Z” is indicated by higher layersignaling, more specifically, “Z” is indicated for the physical downlinkshared channel and physical uplink shared channel by the frequencyhopping configuration for the respective channel, and indicated by thefrequency hopping configuration in the random access response for themachine type communication downlink control channel.

According to a second embodiment, an apparatus may include at least oneprocessor. The apparatus may also include at least one memory includingcomputer program code. The at least one memory and the computer programcode may be configured, with the at least one processor, to cause theapparatus at least to receive parameters for frequency hopping indownlink or uplink. The parameters comprise an “X,” “Y,” and “Z”parameters. “X” corresponds to a duration for which the same physicalresource blocks are used for transmission. “Y” corresponds to afrequency hopping period. “Z” corresponds to a frequency hopping patternindication. The apparatus may also be caused to perform frequencyhopping in accordance with the parameters.

In the apparatus of the second embodiment, the one or more parametersfor frequency hopping are broadcast, configured via radio resourcecontrol signalling or configured via Layer 1 (L1) signalling.

In the apparatus of the second embodiment, “X” and “Y” are based onphysical downlink shared channel or machine type communication downlinkcontrol channel or physical uplink shared channel or physical randomaccess channel repetition levels.

In the apparatus of the second embodiment, “X” is based on a channelestimation filter length.

In the apparatus of the second embodiment, “Y” corresponds to ceiling(K/n). “K” corresponds to a number of repetitions. “n” is an integergreater than or equal to 2, and “n” is the number of hops in one datatransmission configured by an evolved Node B.

In the apparatus of the second embodiment, the values of “X” and “Y” arethe same for all repetition levels. The number of hops is determinedaccording to the repetition number of the related repetition level and“Y”.

In the apparatus of the second embodiment, “X” corresponds to Y−1.

In the apparatus of the second embodiment, “Z” is based on an offset ora predefined pattern for physical downlink shared channel or machinetype communication downlink control channel or physical uplink sharedchannel or physical random access channel frequency hopping.

In the apparatus of the second embodiment, the predefined patternincludes half-bandwidth frequency hopping or one-fourth-bandwidthfrequency hopping.

In the apparatus of the second embodiment, “Z” is the index of a patternof pre-defined PRB blocks, where 6 PRBs constitute a PRB block, forphysical downlink shared channel or physical uplink shared channelfrequency hopping.

In the apparatus of the second embodiment, “Z” is the index of anyconsecutive 6 PRBs, for physical downlink shared channel or physicaluplink shared channel frequency hopping.

In the apparatus of the second embodiment, the position of frequencyhopping is indicated by DCI, where additional bits provide theinformation of the position of the 6 PRBs for each hop.

In the apparatus of the second embodiment, “Z” is indicated by higherlayer signaling, more specifically, “Z” is indicated for the physicaldownlink shared channel and physical uplink shared channel by thefrequency hopping configuration for the respective channel, andindicated by the frequency hopping configuration in the random accessresponse for the MTC downlink control channel.

According to a third embodiment, a computer program product may beembodied on a non-transitory computer readable medium. The computerprogram product may be configured to control a processor to perform aprocess, including receiving, by a machine type communication userequipment, parameters for frequency hopping in downlink and uplink. Theparameters may include an “X,” “Y,” and “Z” parameters. “X” correspondsto a duration for which the same physical resource blocks are used fortransmission. “Y” corresponds to a frequency hopping period. “Z”corresponds to a frequency hopping pattern indication. The process mayalso include performing frequency hopping in accordance with theparameters.

In the computer program product of the third embodiment, the one or moreparameters for frequency hopping are broadcast, configured via radioresource control signalling or configured via Layer 1 (L1) signalling.

In the computer program product of the third embodiment, “X” and “Y” arebased on physical downlink shared channel or machine type communicationdownlink control channel or physical uplink shared channel or physicalrandom access channel repetition levels.

In the computer program product of the third embodiment, “X” is based ona channel estimation filter length.

In the computer program product of the third embodiment, “Y” correspondsto ceiling (K/n). “K” corresponds to a number of repetitions. “n” is aninteger greater than or equal to 2, and “n” is the number of hops in onedata transmission configured by an evolved Node B.

In the computer program product of the third embodiment, the values of“X” and “Y” are the same for all repetition levels, the number of hopsis determined according to the repetition number of the relatedrepetition level and “Y”.

In the computer program product of the third embodiment, “X” correspondsto Y−1.

In the computer program product of the third embodiment, “Z” is based onan offset or a predefined pattern for physical downlink shared channelor machine type communication downlink control channel or physicaluplink shared channel or physical random access channel frequencyhopping.

In the computer program product of the third embodiment, the predefinedpattern includes half-bandwidth frequency hopping orone-fourth-bandwidth frequency hopping.

In the computer program product of the third embodiment, “Z” is theindex of a pattern of pre-defined PRB blocks, where 6 PRBs constitute aPRB block, for physical downlink shared channel or physical uplinkshared channel frequency hopping.

In the computer program product of the third embodiment, “Z” is theindex of any consecutive 6 PRBs, for physical downlink shared channel orphysical uplink shared channel frequency hopping.

In the computer program product of the third embodiment, the position offrequency hopping is indicated by DCI, where additional bits provide theinformation of the position of the 6 PRBs for each hop.

In the computer program product of the third embodiment, “Z” isindicated by higher layer signaling, more specifically, “Z” is indicatedfor the physical downlink shared channel and physical uplink sharedchannel by the frequency hopping configuration for the respectivechannel, and indicated by the frequency hopping configuration in therandom access response for the MTC downlink control channel.

BRIEF DESCRIPTION OF THE DRAWINGS

For proper understanding of the invention, reference should be made tothe accompanying drawings, wherein:

FIG. 1 illustrates a frequency hopping frequency and configuration.

FIG. 2 illustrates frequency hopping with half-system bandwidth.

FIG. 3 illustrates frequency hopping with a physical resource blocks(PRBs) pattern.

FIG. 4 illustrates a flowchart of a method in accordance with certainembodiments of the invention.

FIG. 5 illustrates an apparatus in accordance with certain embodimentsof the invention.

FIG. 6 illustrates an apparatus in accordance with certain embodimentsof the invention.

DETAILED DESCRIPTION

Certain embodiments of the present invention relate to a frequencyhopping method for machine type communication. Certain embodiments ofthe present invention relate to the 3GPP Release 13 Work Item entitled“Further LTE Physical Layer Enhancements for MTC.” One of the objectivesof certain embodiments is to improve coverage enhancement. Anotherobjective may be to implement related techniques such as frequencyhopping, for example.

In RAN1#79 meeting, it was agreed that Release 13 low-cost machine typecommunications (MTC) user equipment (UE) can only transmit and receivedata in a narrow bandwidth (such as a bandwidth of 6 physical resourceblocks (PRBs), for example).

As shown by contribution R1-150255, for the event timer unit channel 1(ETU1 channel), the gain from hopping is negligible at a 10% block errorrate (BLER) point. At the 1% BLER point, there is a gain of up to 1 dB.Such a gain may result in up to a 25% reduction in the number ofrequired repetitions for this channel.

Hence, frequency hopping may be a promising technique for furtherconsideration. For improvement of physical uplink shared channelcoverage, R1-150254 has provided a similar observation. R1-150254 hasdescribed the following: “Observation 2: For PUSCH, cross-subframechannel estimation reduces the number of required repetitionssignificantly. At high coverage enhancement level, increased DMRSdensity and PSD boosting below 1 PRB can also reduce the number ofrequired repetitions significantly. Frequency hopping is also promisingtechniques but requires further study.” As such, frequency hopping maybe a promising technique for enhancing coverage for physical uplinkshared channel (PUSCH) and for physical downlink shared channel (PDSCH).

In RAN1#80 meeting, the following agreements were reached, as describedbelow. PDSCH and PUSCH frequency hopping will be supported when MTC userequipment (UE) is located in enhanced coverage. With regard to thereached agreements, for Release 13 low complexity UE in enhancedcoverage, the following techniques that are related to, at least,unicast PDSCH should be supported.

In order to allow cross-subframe channel estimation, the scheduled PRBis in the same (frequency domain) position during at least X subframes.Assuming that the channel does not vary significantly during those Xsubframes, the channel for that PRB can be estimated by using referencesymbols in all X subframes with the help of an appropriate filter. Thevalue of “X” and the configuration are intended to be studied further.Having the PRB position as the same for X subframes does not precludediscontinuous transmission for unicast PDSCH.

Frequency hopping is supported over the system bandwidth (BW). If/whenfrequency hopping is applied, a frequency location should be switchedafter every Y consecutive subframes, where Y is equal to or larger thanX, assuming that a re-tuning time is included in Y. Configurability isintended to be studied further.

With regard to other agreements that are reached, for physicalchannel(s) carrying UL data repetition (including different redundancyversions (RVs)) for Release 13 low complexity MTC UEs with a coverageenhancement mode, a variety of techniques are supported. For example,the following techniques are supported: (1) Cross-subframe channelestimation, and/or (2) Frequency hopping over system bandwidth acrosssubframes. The network can enable or disable the hopping. The details ofconfiguration are intended to be studied further.

It was agreed that Release 13 low cost MTC UE can only transmit andreceive data in a narrow bandwidth (such as a bandwidth of 6 PRBs, forexample). Considering the agreements of RAN1#80 meeting, PDSCH and PUSCHfor MTC could change the frequency domain location in differentsubframes. Several issues related to frequency hopping may need to beaddressed. For example, frequency hopping patterns for UL and DLphysical channels may need to be addressed. Frequency hoppingconfigurations in UL and DL may need to be addressed.

Based on the RAN1#80 agreements, frequency hopping patterns andconfigurations can be described by three parameters as illustrated byFIG. 1. FIG. 1 illustrates a frequency hopping frequency andconfiguration.

The parameters are described as follows. “X” may correspond to aduration of same PRB position (to enable cross-subframe channelestimation), and the unit of measurement may be a subframe. “Y” maycorrespond to a frequency hopping period (equal to or greater than X,including a re-tuning time), and the unit of measurement may be asubframe. “Z” may correspond to a frequency hopping pattern indication.

Certain embodiments of the present invention may be directed to theconfiguration of (X, Y, Z) parameters for frequency hopping in DL andUL.

With respect to X & Y configuration, X and Y are based on theEnhanced-Physical-Downlink-Control-Channel/Physical-Downlink-Shared-Channelor Physical-Uplink-Shared-Channel/Physical-Random-Access-Channelrepetition level, or based on a coverage enhancement level in UL and DL.The repetition level is configured by the eNB and each transmission isrepeated a pre-defined number of times for each repetition level. Themaximum values of X and Y should be less than the number of repetitionsconfigured for the UE.

Y depends on a channel estimation filter length to allow UE to startcross-subframe channel estimation prior to PDSCH/PUSCH transmission bythe eNB. Cross-subframe channel estimation also depends on the phasecontinuity at the eNB/UE. So, in one embodiment, Y can depend on theassumed phase continuity at the eNB/UE. In one embodiment,Y=ceiling(K/n), where K=number ofrepetition, and “n” is an integergreater than or equal to 2. “n” is a parameter configured by the eNB.There may be one parameter “n” that can be used to calculate X and Y,regardless of the repetition level. In other words, if MTC knows therepetition numbers of all repetition levels, the X and Y will updateautomatically if a repetition level is adjusted. This is more suitablefor the case that frequency hopping pattern is indicated by DCI.

With a second embodiment for X and Y configuration, the values of X andY are the same for all repetition levels and, with the information ofconfigured maximum repetition number for the repetition level, an MTC UEcan derive the number of frequency hops via dividing the repetitionnumber by Y. If repetition level adaptation is allowed, the eNB needs toinform the UE the repetition numbers corresponding to all repetitionlevels; therefore, UE could simply adjust the number of frequency hopswhen the repetition level is updated, in case the half-system-bandwidthfrequency hopping pattern is applied

The value of X may correspond to Y−1, for example, when the re-tuningtime does not exceed a subframe duration. In another embodiment, theinitial X and Y are based on a preamble repetition level that is used ina random access procedure. During an initial system access, the preamblerepetition level is used as a starting point for a UE coverageenhancement level.

With respect to Hopping Pattern Z, with a first embodiment, when an eNBschedules a coverage enhancement MTC UE, the UE can be scheduled in anycontinuous 6 PRBs.

In DL, frequency hopping of enhanced physical downlink control channel(EPDCCH) and PDSCH is implemented by switching a fixed frequencyposition, for example, switching by half of the system bandwidth orone-fourth of the system bandwidth. More specifically, forhalf-bandwidth frequency hopping, the PRB position after frequencyhopping is determined by adding a half-system-bandwidth with the PRBposition prior to the hopping and wrapping around to remain inside thesystem bandwidth.

$n_{{PRB}\mspace{14mu} {hopping}} = \left\{ \begin{matrix}{{\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2}} \right) \cdot {mod}}\; N_{RB}^{DL}} & {{{if}\mspace{14mu} {\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2}} \right) \cdot {mod}}\; N_{RB}^{DL}} \leq {N_{RB}^{DL} - 6}} \\{{{\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2}} \right) \cdot {mod}}\; N_{RB}^{DL}} - 3} & {{{{if}\mspace{14mu} N_{RB}^{DL}} - 6} < {{\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2}} \right) \cdot {mod}}\; N_{RB}^{DL}} \leq {N_{RB}^{DL} - 3}} \\{{{\left. {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2}} \right) \cdot {mod}}\; N_{RB}^{DL}} + 3} & {{{{if}\mspace{14mu} N_{RB}^{DL}} - 3} < {{\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2}} \right) \cdot {mod}}\; N_{RB}^{DL}} \leq N_{RB}^{DL}}\end{matrix} \right.$

N_(RB) ^(DL) is a system bandwidth, expressed in multiple of PRB.n_(first PRB) is the first PRB index of a continuous 6 PRBs before thefrequency hopping. n_(PRB hopping) is the first PRB index of acontinuous 6 PRBs after the frequency hopping.

In UL, the PUSCH or physical random access channel (PRACH) frequencyhopping is similar to PDSCH frequency hopping, and only the PRBsallocated to PUCCH are precluded from system bandwidth to avoidcollision with PUCCH PRBs.

The frequency hopping pattern can be determined as

$n_{{PRB}\mspace{14mu} {hopping}} = \left\{ \begin{matrix}\begin{matrix}{\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2} - N_{RB}^{PUCCH}} \right) \cdot {{mod}\left( {N_{RB}^{DL} - {2 \cdot N_{RB}^{PUCCH}}} \right)}} \\{{{{if}\mspace{14mu} {\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2} - N_{RB}^{PUCCH}} \right) \cdot {{mod}\left( {N_{RB}^{DL} - {2 \cdot N_{RB}^{PUCCH}}} \right)}}} - 3} \leq {N_{RB}^{DL} - {2 \cdot N_{RB}^{PUCCH}} - 6}}\end{matrix} \\{{\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2} - N_{RB}^{PUCCH}} \right) \cdot {{mod}\left( {N_{RB}^{DL} - {2 \cdot N_{RB}^{PUCCH}}} \right)}} - 3} \\{{{{if}\mspace{14mu} N_{RB}^{DL}} - {2 \cdot N_{RB}^{PUCCH}} - 6} < {{\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2} - N_{RB}^{PUCCH}} \right) \cdot {{mod}\left( {N_{RB}^{DL} - {2 \cdot N_{RB}^{PUCCH}}} \right)}} - 3} \leq {N_{RB}^{DL} - {2 \cdot N_{RB}^{PUCCH}}}} \\{{\left( {n_{{first}\mspace{14mu} {PRB}} + {N_{RB}^{DL}/2} - N_{RB}^{PUCCH}} \right) \cdot {{mod}\left( {N_{RB}^{DL} - {2 \cdot N_{RB}^{PUCCH}}} \right)}} + 3} \\{else}\end{matrix} \right.$

N_(RB) ^(PUCCH) are the PRB numbers allocated for PUCCH transmission inhalf of the system bandwidth.

Frequency hopping of EPDCCH, PDSCH, and PUSCH can be configuredseparately by higher layer signalling. The frequency location ofphysical channels can be switched several times according to theconfigured repetition level. Enabling of frequency hopping can beindicated by higher layer signalling, such as by Random Access Response(RAR) or by physical layer signalling. For example, enabling offrequency hopping can be signalled by, for example, 1 bit in downlinkcontrol information (DCI). For PRACH, frequency-hopping-relatedinformation is embedded in the PRACH configuration, including whetherfrequency hopping is enabled or not, X or Y value indication, andfrequency hopping pattern indication such as half-system bandwidthfrequency hopping or one-fourth bandwidth frequency hopping. The PUCCHPRBs are excluded from the system bandwidth. Some potentialspecification impacts on TS36.331 are shown below. Here, it is assumedthat the number of repetitions for each repetition level is alreadydefined.

PRACH-Config information elements -- ASN1START PRACH-ConfigSIB ::=SEQUENCE { rootSequenceIndex INTEGER (0..837), prach-ConfigInfoPRACH-ConfigInfo } PRACH-Config ::= SEQUENCE { rootSequenceIndex INTEGER(0..837), prach-ConfigInfo PRACH-ConfigInfo OPTIONAL -- Need ON }PRACH-ConfigInfo ::= SEQUENCE { prach-ConfigIndex INTEGER (0..63),highSpeedFlag BOOLEAN, zeroCorrelationZoneConfig INTEGER (0..15),prach-FreqOffset INTEGER (0..94) frequency hopping enabling BOOLEANfrquency hopping period INTERGER (0..63) frquency hopping patternINTERGER (0,1) } } -- ASN1STOP

The pattern may also include an offset that depends on a physical cellID (PCI) to randomize inter-cell interference.

With a second embodiment, a MTC UE can only be scheduled withinpredefined 6-PRB regions, according to the system bandwidth. The UL orDL PRB(s) position (after each frequency hopping) is signalled in DCIcarried by EPDCCH (when scheduling PDSCH or PUSCH). Alternatively, thefrequency hopping information can be carried by higher layer signallingwith PDSCH or PUSCH configuration. The frequency hopping information mayinclude the initial 6 PRBs position and duration, the 6 PRBs position ina first frequency hopping and duration, and so on. For EPDCCH frequencyhopping, the PRB(s) position indication can be configured for the UE, interms of the operating 6-PRB allocation, by higher layer signalling,such as RAR signalling.

With a third embodiment, MTC UE can be scheduled in any continuous 6PRBs in the system bandwidth. The UL or DL PRB(s) position afterfrequency hopping is signaled in DCI carried by EPDCCH (scheduling PDSCHor PUSCH). Alternatively, the frequency hopping information can becarried by higher layer signalling with PDSCH or PUSCH configuration,such as the initial 6 PRBs position and duration, 6 PRBs position infirst frequency hopping and duration, and so on. For EPDCCH frequencyhopping, the PRB position indication can be configured for the UE, interms of the operating 6-PRB allocation, by higher layer signalling suchas RAR signalling.

Further, with certain embodiments of the present invention, when hoppingis applied on one link (DL or UL), the same pattern is alsosimultaneously applied on the other link. In case UE needs to maintainthe same Tx-Rx separation, certain embodiments may synchronize hopping.

Certain embodiments of the present invention implement UL and DLfrequency hopping for low cost MTC in coverage mode.

With respect to X & Y Configuration, configuration of X & Y may bestraightforward.

In one embodiment, X and Y may be based on a EPDCCH/PDSCH repetitionlevel, a PUSCH/PRACH repetition level, or based on a configured coverageenhancement level in UL and DL. In another embodiment, X and Y areseparately configured for EPDCCH, PDSCH, PUSCH, and PRACH.

In another embodiment, X and Y can either be semi-statically configured,dynamically assigned, and/or derived from another transmission. Forexample, X & Y for Msg3 transmission can be derived from the number ofPRACH repetitions.

In another embodiment, X and Y are dependent on the type oftransmission. For example, X & Y could be different for a RAR, Paging,unicast, System Information Block (SIB), or broadcast channel.

In another embodiment, Y=ceiling(K/n), where K=number of repetitions,and n is an integer greater than or equal to 2 (that is configured byeNB).

One parameter “n” can be specified that can be used to calculate X andY, regardless of the repetition level. In other words, the X and Yvalues may update automatically if the repetition level is adjusted.

With respect to Hopping Pattern Z, in one embodiment, frequency hoppingis based on an offset or a predefined pattern. In another embodiment,the offset is based on the system bandwidth, is provided in the DCI, isbased on a physical cell ID, and/or is configured via higher layersignalling.

In another embodiment, the predefined pattern may be based on a systembandwidth or a physical cell ID, and the hopping information may beconfigured via higher layer signalling.

In one embodiment, when hopping is applied on one link (DL or UL), thesame pattern is also simultaneously applied on the other link.

With a first embodiment, the MTC UE can be scheduled in any 6 continuousPRBs by eNB, if frequency hopping is enabled. After repeatedtransmission with a predefined number of repetitions in the same 6 PRBs,the MTC UE may transmit or receive in another 6 PRBs. The frequencylocation may be shifted by half the system bandwidth. For instance, ifthe system bandwidth is 100 PRBs and the PDSCH is initially transmittedin PRB #5-12, then after the frequency hopping, the PDSCH will betransmitted in PRB #55-62. Also, frequency hopping can be performedseveral times according to a repetition level. Then, after anotherfrequency hopping, the PDSCH will be transmitted again in PRB #5-12.

FIG. 2 illustrates frequency hopping with a half-system-bandwidth. Asillustrated by FIG. 2, with repetition level 2, frequency hopping isperformed twice. Also according to these embodiments, the frequencyhopping configuration can be different for different MTC UEs.

With this embodiment, different MTC UEs (or UEs in different repetitionlevels) could get the most of the frequency diversity gains. It may beeasier for MTC UE implementation.

With a second embodiment of the present invention, the available 6 PRBsfor MTC UE is determined according to the center 6 PRBs. The central 6PRBs may be used for PBCH/SIB/Paging reception, and the 6 PRBs allocatedto MTC UE are not overlapped with the center 6 PRBs. If the systembandwidth is 20 MHz (corresponding to 100 PRBs, for example), each halfof the bandwidth could have 47 PRBs available for MTC usage. 7×6 PRBscan be allocated to MTC UEs, and 5 PRBs may not be used within thehalf-bandwidth. So, there are a total of 15 (7+1+7) PRB blocks for MTCusage. With these embodiments, 4 bits are needed to indicate thefrequency location of 6 PRBs for each hopping. The 4×m bits of hoppinginformation can be included in DCI (carried by EPDCCH), where m is thenumber of hops for one data transmission. If frequency hoppinginformation is accompanying an indication of MTC operating PRBs, thehopping information could comprise {initial 6 PRBs position, 6 PRBsposition in first hopping, 6 PRBs position in second hopping . . . }. Inanother way, the 6-PRB allocation does not depend on isolating thecentral 6 PRBs; for example, if 6 PRBs constitute a PRB block, there areat most 16 PRB blocks available for MTC usage, and again 4 bits areneeded in DCI for each frequency hopping.

For this embodiment, the frequency position for each hopping in one datatransmission can be flexibly determined by the eNB. However, theavailable PRBs for MTC usage are less than the first embodiment and moreDCI bits are required for frequency hopping. The illustration of asecond embodiment is illustrated by FIG. 3. FIG. 3 illustrates frequencyhopping with a PRBs pattern.

With a third embodiment, there may be no PRBs allocation restrictionsfor MTC, the first PRB index of the allocated PRB block can be flexiblyconfigured by the eNB. However, more bits in DCI are required toindicate the PRB position after the hopping. The eNB has moreflexibility to scheduling MTC UE and hopping. But, with an increase inMTC devices, the eNB scheduling could get more complex and the frequencydiversity gain will decrease.

For the frequency hopping period and duration determination, certainembodiments of the present invention may be robust and automaticallyadapted to implicitly update a repetition level, and additional RadioResource Control (RRC) signaling may not be required.

For the frequency hopping patterns, the first embodiment has littleimpact on standards, while most of frequency diversity gains can beachieved.

The second embodiment may allow the eNB to have more flexibility toconfigure the frequency position location. The cost could be an increasein DCI size, and the EPDCCH transmission may need more repetition.

The third embodiment may be more flexible than the second embodiment,but the third embodiment may need to add more bits in DCI.

FIG. 4 illustrates a flowchart of a method in accordance with certainembodiments of the invention. The method illustrated in FIG. 4 includes,at 410, receiving, by a machine type communication user equipment,parameters for frequency hopping in downlink or uplink. The parameterscomprise an “X,” “Y,” and “Z” parameters. “X” corresponds to a durationfor which the same physical resource blocks are used for transmission.“Y” corresponds to a frequency hopping period, and “Z” corresponds to afrequency hopping pattern indication. The method may also include, at420, performing frequency hopping in accordance with the parameters.

FIG. 5 illustrates an apparatus in accordance with certain embodimentsof the invention. In one embodiment, the apparatus can be a userequipment, a base station, and/or a MTC device, for example. Theapparatus can be a network node. Apparatus 10 can include a processor 22for processing information and executing instructions or operations.Processor 22 can be any type of general or specific purpose processor.While a single processor 22 is shown in FIG. 5, multiple processors canbe utilized according to other embodiments. Processor 22 can alsoinclude one or more of general-purpose computers, special purposecomputers, microprocessors, digital signal processors (DSPs),field-programmable gate arrays (FPGAs), application-specific integratedcircuits (ASICs), and processors based on a multi-core processorarchitecture, as examples.

Apparatus 10 can further include a memory 14, coupled to processor 22,for storing information and instructions that can be executed byprocessor 22. Memory 14 can be one or more memories and of any typesuitable to the local application environment, and can be implementedusing any suitable volatile or nonvolatile data storage technology suchas a semiconductor-based memory device, a magnetic memory device andsystem, an optical memory device and system, fixed memory, and removablememory. For example, memory 14 include any combination of random accessmemory (RAM), read only memory (ROM), static storage such as a magneticor optical disk, or any other type of non-transitory machine or computerreadable media. The instructions stored in memory 14 can include programinstructions or computer program code that, when executed by processor22, enable the apparatus 10 to perform tasks as described herein.

Apparatus 10 can also include one or more antennas (not shown) fortransmitting and receiving signals and/or data to and from apparatus 10.Apparatus 10 can further include a transceiver 28 that modulatesinformation on to a carrier waveform for transmission by the antenna(s)and demodulates information received via the antenna(s) for furtherprocessing by other elements of apparatus 10. In other embodiments,transceiver 28 can be capable of transmitting and receiving signals ordata directly.

Processor 22 can perform functions associated with the operation ofapparatus 10 including, without limitation, precoding of antennagain/phase parameters, encoding and decoding of individual bits forminga communication message, formatting of information, and overall controlof the apparatus 10, including processes related to management ofcommunication resources.

For example, apparatus 10 may receive parameters for frequency hoppingin downlink or uplink. The parameters may include an “X,” “Y,” and “Z”parameters. “X” may correspond to a duration for which the same physicalresource blocks are used for transmission. “Y” may correspond to afrequency hopping period. “Z” may correspond to a frequency hoppingpattern indication. Apparatus 10 may also perform frequency hopping inaccordance with the parameters.

In an embodiment, memory 14 can store software modules that providefunctionality when executed by processor 22. The modules can include anoperating system 15 that provides operating system functionality forapparatus 10. The memory can also store one or more functional modules18, such as an application or program, to provide additionalfunctionality for apparatus 10. The components of apparatus 10 can beimplemented in hardware, or as any suitable combination of hardware andsoftware.

FIG. 6 illustrates an apparatus in accordance with certain embodimentsof the invention. Apparatus 600 can be a network element/entity such asa user equipment, for example. Apparatus 600 can include a receivingunit 610 that receives, by a machine type communication user equipment,parameters for frequency hopping in downlink or uplink, wherein theparameters comprise an “X,” “Y,” and “Z” parameters, “X” corresponds toa duration for which the same physical resource blocks are used fortransmission. “Y” corresponds to a frequency hopping period, and “Z”corresponds to a frequency hopping pattern indication. Apparatus 600 canalso include a performing unit 620 that performs frequency hopping inaccordance with the parameters.

The described features, advantages, and characteristics of the inventioncan be combined in any suitable manner in one or more embodiments. Oneskilled in the relevant art will recognize that the invention can bepracticed without one or more of the specific features or advantages ofa particular embodiment. In other instances, additional features andadvantages can be recognized in certain embodiments that may not bepresent in all embodiments of the invention. One having ordinary skillin the art will readily understand that the invention as discussed abovemay be practiced with steps in a different order, and/or with hardwareelements in configurations which are different than those which aredisclosed. Therefore, although the invention has been described basedupon these preferred embodiments, it would be apparent to those of skillin the art that certain modifications, variations, and alternativeconstructions would be apparent, while remaining within the spirit andscope of the invention.

1. A method, comprising: receiving, by a machine type communication userequipment, parameters for frequency hopping in downlink or uplink,wherein the parameters comprise an “X,” “Y,” and “Z” parameters, “X”corresponds to a duration for which the same physical resource blocksare used for transmission, “Y” corresponds to a frequency hoppingperiod, and “Z” corresponds to a frequency hopping pattern indication;and performing frequency hopping in accordance with the parameters,wherein “X” and “Y” are based on physical downlink shared channel ormachine type communication downlink control channel or physical uplinkshared channel or physical random access channel repetition levels. 2.The method according to claim 1, wherein the one or more parameters forfrequency hopping are broadcast, configured via radio resource controlsignalling or configured via Layer 1 (L1) signalling.
 3. (canceled) 4.The method according to claim 1, wherein “X” is based on a channelestimation filter length.
 5. The method according to claim 1, wherein“Y” corresponds to ceiling (K/n), “K” corresponds to a number ofrepetitions, “n” is an integer greater than or equal to 2, and “n” isthe number of hops in one data transmission configured by an evolvedNode B.
 6. The method according to claim 1, wherein the values of “X”and “Y” are the same for all repetition levels, the number of hops isdetermined according to the repetition number of the related repetitionlevel and “Y”.
 7. The method according to claim 1, wherein “X”corresponds to Y−1.
 8. The method according to claim 1, wherein “Z” isbased on an offset or a predefined pattern for physical downlink sharedchannel or machine type communication downlink control channel orphysical uplink shared channel or physical random access channelfrequency hopping.
 9. The method according to claim 8, wherein, thepredefined pattern includes half-bandwidth frequency hopping orone-fourth-bandwidth frequency hopping.
 10. The method according toclaim 1, wherein “Z” comprises an index of a pattern of pre-defined PRBblocks, where 6 PRBs constitute a PRB block, for physical downlinkshared channel or physical uplink shared channel frequency hopping. 11.The method according to claim 1, wherein “Z” comprises an index of anyconsecutive 6 PRBs, for physical downlink shared channel or physicaluplink shared channel frequency hopping.
 12. The method according toclaim 10, wherein a position of frequency hopping is indicated by DCI,where additional bits provide the information of the position of the 6PRBs for each hop.
 13. The method according to claim 1, wherein “Z” isindicated by higher layer signaling, “Z” is indicated for the physicaldownlink shared channel and physical uplink shared channel by thefrequency hopping configuration for the respective channel, andindicated by the frequency hopping configuration in the random accessresponse for the machine type communication downlink control channel.14. An apparatus, comprising: at least one processor; and at least onememory including computer program code, the at least one memory and thecomputer program code configured, with the at least one processor, tocause the apparatus at least to receive parameters for frequency hoppingin downlink or uplink, wherein the parameters comprise an “X,” “Y,” and“Z” parameters, “X” corresponds to a duration for which the samephysical resource blocks are used for transmission, “Y” corresponds to afrequency hopping period, and “Z” corresponds to a frequency hoppingpattern indication; and perform frequency hopping in accordance with theparameters, wherein “X” and “Y” are based on physical downlink sharedchannel or machine type communication downlink control channel orphysical uplink shared channel or physical random access channelrepetition levels.
 15. The apparatus according to claim 14, wherein theone or more parameters for frequency hopping are broadcast, configuredvia radio resource control signalling or configured via Layer 1 (L1)signalling.
 16. (canceled)
 17. The apparatus according to claim 14,wherein “X” is based on a channel estimation filter length.
 18. Theapparatus according to claim 14, wherein “Y” corresponds to ceiling(K/n), “K” corresponds to a number of repetitions, “n” comprising aninteger greater than or equal to 2, and “n” comprises a number of hopsin one data transmission configured by an evolved Node B.
 19. Theapparatus according to claim 14, wherein values of “X” and “Y” are samefor all repetition levels, and a number of hops is determined accordingto a repetition number of a related repetition level and “Y”.
 20. Theapparatus according to claim 14, wherein “X” corresponds to Y−1.
 21. Theapparatus according to claim 14, wherein “Z” is based on an offset or apredefined pattern for physical downlink shared channel or machine typecommunication downlink control channel or physical uplink shared channelor physical random access channel frequency hopping.
 22. The apparatusaccording to claim 21, wherein the predefined pattern includeshalf-bandwidth frequency hopping or one-fourth-bandwidth frequencyhopping.
 23. The apparatus according to claim 14, wherein “Z” comprisesan index of a pattern of pre-defined PRB blocks, where 6 PRBs constitutea PRB block, for physical downlink shared channel or physical uplinkshared channel frequency hopping.
 24. The apparatus according to claim14, wherein “Z” comprises an index of any consecutive 6 PRBs, forphysical downlink shared channel or physical uplink shared channelfrequency hopping.
 25. The apparatus according to claim 23, wherein aposition of frequency hopping is indicated by DCI, where additional bitsprovide information of the position of the 6 PRBs for each hop.
 26. Theapparatus according to claim 14, wherein “Z” is indicated by higherlayer signaling, “Z” is indicated for the physical downlink sharedchannel and physical uplink shared channel by the frequency hoppingconfiguration for the respective channel, and indicated by the frequencyhopping configuration in the random access response for the machine typecommunication downlink control channel.
 27. A computer program product,embodied on a non-transitory computer readable medium, the computerprogram product configured to control a processor to perform a process,comprising: receiving, by a machine type communication user equipment,parameters for frequency hopping in downlink and uplink, wherein theparameters comprise an “X,” “Y,” and “Z” parameters, “X” corresponds toa duration for which the same physical resource blocks are used fortransmission, “Y” corresponds to a frequency hopping period, and “Z”corresponds to a frequency hopping pattern indication; and performingfrequency hopping in accordance with the parameters, wherein “X” and “Y”are based on physical downlink shared channel or machine typecommunication downlink control channel or physical uplink shared channelor physical random access channel repetition levels.
 28. The computerprogram product according to claim 27, wherein the one or moreparameters for frequency hopping are broadcast, configured via radioresource control signalling or configured via Layer 1 (L1) signalling.29. (canceled)
 30. The computer program product according to claim 27,wherein “X” is based on a channel estimation filter length.
 31. Thecomputer program product according to claim 27, wherein “Y” correspondsto ceiling (K/n), “K” corresponds to a number of repetitions, “n” is aninteger greater than or equal to 2, and “n” is the number of hops in onedata transmission configured by an evolved Node B.
 32. The computerprogram product according to claim 1, wherein the values of “X” and “Y”are the same for all repetition levels, a number of hops is determinedaccording to the repetition number of the related repetition level and“Y”.
 33. The computer program product according to claim 27, wherein “X”corresponds to Y−1.
 34. The computer program product according to claim27, wherein “Z” is based on an offset or a predefined pattern forphysical downlink shared channel or machine type communication downlinkcontrol channel or physical uplink shared channel or physical randomaccess channel frequency hopping.
 35. The computer program productaccording to claim 34, wherein, the predefined pattern includeshalf-bandwidth frequency hopping or one-fourth-bandwidth frequencyhopping.
 36. The computer program product according to claim 27, wherein“Z” comprises an index of a pattern of pre-defined PRB blocks, where 6PRBs constitute a PRB block, for physical downlink shared channel orphysical uplink shared channel frequency hopping.
 37. The computerprogram product according to claim 27, wherein “Z” is the index of anyconsecutive 6 PRBs, for physical downlink shared channel or physicaluplink shared channel frequency hopping.
 38. The computer programproduct according to claim 36, wherein a position of frequency hoppingis indicated by DCI, where additional bits provide the information ofthe position of the 6 PRBs for each hop.
 39. The computer programproduct according to claim 27, wherein “Z” is indicated by higher layersignaling, “Z” is indicated for the physical downlink shared channel andphysical uplink shared channel by the frequency hopping configurationfor the respective channel, and indicated by the frequency hoppingconfiguration in the random access response for the machine typecommunication downlink control channel.